So I am, and have always been (since my first SLR in grade school), a Pentax shooter - a Pentaxian.
There are many reasons why I have stuck with Pentax... First and foremost, Pentax has ALWAYS focused on the photographer (IMHO).
Pentax has not chased the consumer market... they have not given in to the glitz and glam of the mass market of consumer sales that artificially inflated numbers for other major camera companies (and have, therefore, not had to struggle to explain to investors the sudden plummet of market share when those consumers flocked to camera phones - last I saw [though I've not verified this] Pentax is actually up 4% while the others are down 20%+).
While the weather proofing of Pentax is not a direct reason, it has always been a happy circumstance... as is the fact that I can still use all my 35 year old K-Mount glass right along with my spankin' new glass on my snappy new K-Mount K3 DSLR. These two things are not only of huge benefit but also just totally cool!
A camera is a rather simple device... photographers are rather simple folk...
We need a box that we can put some light sensitive material (film or sensor) in and a hole in said box which we can open and close in a controlled fashion.
Aperture (the hole), Shutter Speed (the controlled opening of said hole)... and ISO (be it film or sensor - effectively the light sensitive material - and we get to choose the light sensitivity of said material).
Literally, that's it... that IS a camera.
All the other whizbang and flibertygiberty is great and all - but not actually necessary.
Auto Focus: film cameras captured amazing action shots long before auto focus. I still use manual quite frequently.
Internal Light Meters: film cameras captured amazing dynamic images long before internal light meters... and really the light meter is an imperfect guide whose limited ability a photographer needs to learn how to compensate for.
In Camera Processing: dark rooms processed all those action and dynamic shots long before internal processing existed... the dark room was an amazing place.
Come to think of it, the fact that there is a popular package called "light"-room is kind of odd since EVERY ability in it is named after and replicates tasks done in a "dark" room. (Literally - all the 'magic' we do today on a computer was done to film images LONG before 'digital' existed.)
EVERY photo is post processed. Either your camera does it internally (if you shoot JPG) or you do it externally (if you shoot RAW). This is not even a debate. If you have a JPG picture it was post processed. Either your camera did it or you did it - but it was post processed.
Pentax has added one very nice package, IMHO, to these very few necessities in that the control of those things is very easily accessed and adjusted... without moving my eye away from the viewfinder... and without moving my hands - my fingers tend to rest exactly where the adjustments for those things are.
That package, that focus on the photographer and what we need convenient and reliable access to, is why I have been a lifelong Pentaxian.
Yes, Pentax has all the other whizbang just like everyone else - and I can admit that I like to futz with all that whizbang now and again on my Pentax gear... but through it all Pentax has maintained that most important singular focus on... well... Me... the Photographer!
Now, before anyone gets their knickers in a knot, I am not saying that you should not love your Nikon or Canon or Fuji or Sony or whatever you shoot.
Pentax works for me... Pentax makes my photography enjoyable.
What's most important is that you shoot... whatever you shoot...
I always have and will always recommend Pentax because of that dedication to the photographer - to photography... to staying true to what they are and who they serve... photographers. Specifically, Pentaxians.
And that is why Pentaxians exist... in direct response to Pentax's dedication to us we have remained dedicated to Pentax. Pure and Simple.
Pentax has never sought the limelight (literally - great company but never an attention hog - they really have an amazing history if you look into it)... they have always stayed focused on helping the photographer capture the light.
Ahhh - see what I did there? That was accidentally on purpose - but soooooo true! ;)
Okay, so that was my Pentax spiel...
Now how I use them... And what brought me to this particular topic.
I added video to my arsenal - okay, not Pentax video... GoPro.
I LOVE to shoot nature and I LOVE to shoot nature from my kayak.
But how to do that somewhat safely - weather proofing aside...
Build a custom rig, of course!
I can release any of the three in a split second but they remain tethered with the 'safely cords' you see connected to each in the images.
I can also have all three locked in while I paddle so no cameras flopping about while the kayak is in motion.
And this rig is how I capture images like this (below) without waders... ;)
Yes, Pentax is now by Ricoh.
So, full discolsore, I also love Ricoh production imaging equipment! I actually print my images and all the graphic design I do on a Ricoh 9100 Digital Press and a Ricoh L4160 Wide Format.
Second full disclosure, prior to my first 35mm SLR (a Pentax K1000) I shot various older non-SLR cameras - among them were a VERY old Medium format (120 - 6x6) that my Great Grandparents had and a little 110 camera... but my first 35mm SLR was that Pentax K1000 which I still shoot b/w on every so often.